The epoxidation of olefins is a well known process practiced on a large industrial scale, for example see the Kirk-Othmer Encyclopedia of Chemical Technology, 3rd Ed., vol. 9, John Wiley & Sons, New York, 1980, p. 251-266. The most common method of epoxidation is the direct epoxidation of the olefin with an oxidizing agent such as a peracid, hydrogen peroxide or hypochlorous acid.
However, this method is usually not applicable to fluorinated olefins; other methods, which usually require more than one step, can be used to produce fluorine containing epoxides. These are reviewed by P. Tarrant, et al., in Fluorine Chemistry Reviews, vol. 5, Marcel Dekker, Inc., New York, 1971, p. 77-85, and specific examples are found in French Patent 2,529,890A, Japanese Patent 52-136,107 and USSR Patent No. 390,084. It is believed that the fluorinated olefins do not form epoxides in simple epoxidation reactions usually applicable to most olefins because of the electron deficient nature of the olefinic bond, caused by the presence of the fluorine atoms. This inability to undergo simple epoxidation reactions is illustrated hereinafter in Example 6.
S. Rozen and M. Brand, Angew. Chem. Int. Ed. Engl., vol. 25, 554-555 (1986) describe the direct epoxidation of olefins using a mixture of (elemental) fluorine, water and acetonitrile. The utility of this reaction with fluorinated olefins is neither discussed nor disclosed.
Fluorine containing epoxides are of special interest in polymer technology as they give rise to polymers with desirable properties. For example, D. D. Smith, et al., Ind. Eng. Chem., vol. 49, pg. 1241-1246 (1957), report such polymers are excellent low load lubricants. Thus a need exists for a direct efficient epoxidation process for fluorine containing olefins.
It is therefore an object of the present invention to provide a process for the direct epoxidation of fluorine containing olefins.